Answer:
25.89 × 10²³ molecules
Explanation:
Given data:
Mass of CoCl₂ = 560 g
Number of molecules present = ?
Solution:
Number of moles of CoCl₂:
Number of moles = mass/molar mass
Number of moles = 560 g/ 129.84 g/mol
Number of moles = 4.3 mol
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ molecules
4.3 mol × 6.022 × 10²³ molecules /1 mol
25.89 × 10²³ molecules
They are found in group 3 of the periodic table.
<span>Both provide approaches to confirming the result of experimentation. Repetition can be developed by one scientist or team continually achieving the expected result but replication requires an independent person or team shows thay can arrive at the same answer independently</span>
Answer:
The IUPAC name of the compound has already been given which is 2,2-dimethyl-4-ethylheptane.
Explanation:
The IUPAC (International Union of Pure and Applied Chemistry) is an authority in chemistry that provides a guideline and standardized methods in the naming of compounds formed from the periodic table.
In order the give an IUPAC name to a compound, certain steps needs to be followed, these includes:
--> Identify the functional group in the compound as this will form the suffix. For example if the functional group is an alkane the suffix will be -ane.
--> Identify the longest carbon chain (it may not be a straight chain) that contains the functional group. This forms the prefix. Example: if the longest carbon chain is 7 carbon atoms then the prefix will be hept-
--> All the carbons of the longest chain should be numbered
--> Identify branched groups on the chain and name them according to the number of carbon atoms. They usually end with -yl.
--> Finally, combine the elements of the name is a single word.
The structural formula of the IUPAC compound can be found in the attached file for a better understanding. The branched groups are circled.
The system is isothermal, so we use the formula:
(delta)G = (delta)H - T (delta) S
Plugging in the given values:
(delta)G = -220 kJ/ mol - (1000K) (-0.05 kJ/mol K)
(delta)G = -170 kJ/mol
If we take a basis of 1 mol, the answer is
D. -170 kJ